x-y=7
=>x=y+7
\(x^2+y^2=13\)
\(\Leftrightarrow y^2+14y+49+y^2-13=0\)
\(\Leftrightarrow2y^2+14y+36=0\)
\(\Leftrightarrow y^2+7y+18=0\)(vô lý)
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giải hpt sau
a) \(\left\{{}\begin{matrix}x+y+xy=7\\x^2+y^2+xy=13\end{matrix}\right.\)
b)\(\left\{{}\begin{matrix}x^2+y^2=52\\\dfrac{1}{x}+\dfrac{1}{y}=\dfrac{5}{12}\end{matrix}\right.\)
1. Giải các hpt sau:
a, left{{}begin{matrix}x-y43x+4y19end{matrix}right. b, left{{}begin{matrix}x-sqrt{3y}sqrt{3}sqrt{3x}+y7end{matrix}right.
2. Giải các hpt sau:
a, left{{}begin{matrix}2-left(x-yright)-3left(x+yright)53left(x-yright)+5left(x+yright)-2end{matrix}right. b, left{{}begin{matrix}dfrac{2}{x-2}+dfrac{2}{y-1}2dfrac{2}{x-2}-dfrac{3}{y-1}1end{matrix}right.
c, left{{}begin{matrix}x+y24dfrac{x}...
Đọc tiếp
1. Giải các hpt sau:
a, \(\left\{{}\begin{matrix}x-y=4\\3x+4y=19\end{matrix}\right.\) b, \(\left\{{}\begin{matrix}x-\sqrt{3y}=\sqrt{3}\\\sqrt{3x}+y=7\end{matrix}\right.\)
2. Giải các hpt sau:
a, \(\left\{{}\begin{matrix}2-\left(x-y\right)-3\left(x+y\right)=5\\3\left(x-y\right)+5\left(x+y\right)=-2\end{matrix}\right.\) b, \(\left\{{}\begin{matrix}\dfrac{2}{x-2}+\dfrac{2}{y-1}=2\\\dfrac{2}{x-2}-\dfrac{3}{y-1}=1\end{matrix}\right.\)
c, \(\left\{{}\begin{matrix}x+y=24\\\dfrac{x}{9}+\dfrac{y}{27}=2\dfrac{8}{9}\end{matrix}\right.\) d, \(\left\{{}\begin{matrix}\sqrt{x-1}-3\sqrt{y+2}=2\\2\sqrt{x-1}+5\sqrt{y+2=15}\end{matrix}\right.\)
3. Cho hpt \(\left\{{}\begin{matrix}\left(m+1\right)x-y=3\\mx+y=m\end{matrix}\right.\)
a, Giải hpt khi m=\(\sqrt{2}\)
b, tìm giá trị của m để hpt có nghiệm duy nhất thỏa mãn: x+y>0
giải hpt: a,\(\left\{{}\begin{matrix}x^2+y^2+xy=7\\x^4+y^4+x^2y^2=21\end{matrix}\right.\) b,\(\left\{{}\begin{matrix}x+y+\dfrac{1}{x}+\dfrac{1}{y}=7\\x^2-y^2+\dfrac{1}{x^2}-\dfrac{1}{y^2}=21\end{matrix}\right.\)
Giải HPT:
\(\left\{{}\begin{matrix}\left|y+\frac{1}{x}\right|+\left|\frac{13}{6}+x-y\right|=\frac{13}{6}+x+\frac{1}{x}\\x^2+y^2=36\end{matrix}\right.\)
giải hpt: \(\left\{{}\begin{matrix}\left(x+y\right)^2\left(8x^2+8y^2+4xy-13\right)+5=0\\2x+\frac{1}{x+y}=1\end{matrix}\right.\)
giải hpt \(\left\{{}\begin{matrix}x^2-\left(x-1\right)\sqrt{y+2}+3x=4\\\sqrt{x^2+8x+13}+\sqrt{10-y}=3\end{matrix}\right.\)
\(\left\{{}\begin{matrix}x^2+xy+y^2=19\left(x-y\right)^2\\x^2-xy+y^2=7\left(x-y\right)\end{matrix}\right.\)
giải hpt
Giải hpt :
\(\left\{{}\begin{matrix}\frac{x^2+1}{y}+x+y=4\\\left(x+y\right)^2-2\left(\frac{x^2+1}{y}\right)=7\end{matrix}\right.\)
Giải hpt:
\(\left\{{}\begin{matrix}4xy+4\left(x^2+y^2\right)+\frac{3}{\left(x+y\right)^2}=\frac{85}{3}\\2x+\frac{1}{x+y}=\frac{13}{3}\end{matrix}\right.\)